For almost two months we endured (and let’s face it, enjoyed) camp life at its fullest; sleeping on the ice every night, falling into countless water filled holes, enduring the discomforts of cold-numbed toes and keeping up with the seemingly endless treadmill of camp maintenance… But at the end of the day, it was these guys, the “Ice Algae”, that were the true stars of the show!

The picture above is an image of what we see when we look down the microscope at our surface ice samples. Dark-coloured ice algae clearly dominate the sample. Typically we estimated that there were tens of thousands of algal cells in every milliliter of sample. When you bulk these samples up to liters and gallons, and then to the volume of surface ice found within biologically active area of the Greenland Ice Sheet (currently estimated at >400,000 km2), we’re looking at some serious cell numbers. As Marek Stibal explained previously, these guys are packed with a dark purple-brown pigment that protects them from sunlight, but also causes the darkening of the ice surface.

So, were we pleased with our field season? Definitely! Once we had figured out the best way to interpret the environment, we set about to amass as much data as we could, so that any conclusions that are drawn are as robust as possible. Overall we took around 600 samples for biological analysis, over 2000 close range spectral readings and, most amazingly, we individually counted around 94,000 algal cells in the field. This, on top of keeping a well-oiled camp going, kept us more than busy over the summer.

Now that we are back from our field work, our next mission is to interpret just how much albedo change is due to the darkening effect of algal growth on the ice surface, and furthermore, how much this darkening is contributing towards ice melt. In addition, we also intend to use laboratory analyses in Copenhagen to look into some of the more intricate components of the surface ice ecology that we have been living alongside all summer.

About the author Karen Cameron

Dr Karen Cameron is a microbial ecologist working in the Department of Geochemistry at the Geological Survey of Denmark and Greenland. Her previous research has focused on biogeochemical interactions that occur within supraglacial and subglacial environments, and on the biogeographical variability of glacial associated microbial communities.